This invention relates to hampers, and more particularly to a hamper having a mechanism which permits lifting of the bottom of the hamper upwardly toward the mouth of the hamper.
Hampers of these types are useful in post office mail sorting operations, laundries, and other places in industry where a supply of articles to be worked on is near a standing operator who must dig his hand into the hamper to remove the objects. It is apparent that articles present near the top of the sack are readily accessible to the operator. However, as the load is depleted, it becomes necessary for the operator to continuously reach down into the sack in order to obtain its contents.
Various attempts have been made in the prior art to bring the sack contents near the bottom of the sack upward toward the mouth region by raising the sack bottom. For example, in my U.S. Pat. No. 3,310,089, I described a hamper having a frame with a sack depending from the frame. A horizontal ring is positioned around the peripheral wall of the sack spaced between its mouth and its bottom. Ropes are connected to opposite sides of the ring and pass upwardly and to the upper edge of the frame. The ropes can be pulled over the frame edge thereby raising the ring so that the portion beneath the ring is brought upwardly toward the mouth of the sack.
In my U.S. Pat. No. 3,215,182, there is provided another type of a hamper also utilizing rope for aiding in bringing the lower portion of the hamper upward towards its mouth. In that patent, a transverse bar is placed along the bottom of the sack and a rope arrangement is interconnected between the bar and the upper frame using a pulley and tackle arrangement. The rope passes over the upper edge of the frame. As the rope is pulled over the edge, the transverse bar is pulled upwardly to bring the bottom of the sack towards the mouth.
In both of these arrangements, the amount of rope necessary to pull the bottom upward is quite considerable. This is especially the case when dealing with heavy loads which are to be placed into the hampers. Because of such heavy loads, a pulley arrangement must be utilized in order to achieve a sufficient mechanical advantage. In order to achieve this mechanical advantage, the length of the rope drawn over the frame edge is quite considerable. The length of rope produces a disadvantage in that the rope has a tendency of getting tangled, sprawling, and causing accidents. Alternately, the rope must be gathered up and dropped into the container in order to avoid possible tripping accidents, but then the rope itself gets lost and is inaccessible for use.
Other prior art arrangements which have tried to bring the bottom of the sack upward towards its mouth have utilized springs. Such springs bias the bottom of the sack upwardly. By way of example, U.S. Pat. No. 2,411, 643, discloses a complex bobbin receiver having a flat bottom plate which is connected to elastics located within the bag. U.S. Pat. No. 3,168,271 discloses a clothes hamper having springs located within each of its supporting posts and projects partially into base legs so that the bag support is constantly biased upwardly by the force of the springs.
One problem with using biasing springs concerns the adjustment of the springs to the type of weight to be received. For example, if a spring of a fixed tension is utilized, the device can only raise or lift a limited range of contents. A low tension spring will lift only contents of light weight. A high tension spring will lift contents of heavy weight. A platform with a low tension spring will not be able to raise a heavy load. On the other hand, a platform supported by a high tension spring cannot be depressed by lightweight objects thrown into it. As a result, a continuous supply of such lightweight objects will not lower the bottom of the hamper and the hamper will not be able to be filled.
This problem is especially important in the case of hampers being used in connection with mail sorting operations. The size and weight of the packages and envelopes thrown into the hampers vary greatly. In some cases, heavy packages are placed into the sack which would tend to push the spring supported sack down to its extended position and prevent reaching the heavy packages. On the other hand, frequently only light weight packages are thrown in, and the sack will hardly lower at all so the bottom of the sack will continuously remain in its upward raised position.
Accordingly, prior art hampers have been most awkward in their ability to accommodate both heavy and light loads, and at the same time to permit the bottom of the sack to be brought upward near the mouth of the sack to facilitate utilization of the sack by means of the operator.
Still a further problem concerns the ability to modify existing hampers in order to permit them to have the raisability feature. Most hampers having lifting apparatus require that the lifting apparatus be included directly within the original manufacture of the hamper. For example the aforementioned patents utilizing biasing springs all require that the springs be included within portions of the supporting frame and accordingly the basic hamper itself must be originally manufactured with the springs. It is not feasible to modify an existing hamper in order to receive the springs of the aforementioned prior art designs. As a result, any existing hampers without a suitable lifting apparatus cannot be modified in order to permit the lower portion of the sack to be raised when weighted down by loads of wide ranging weights.